Quote Originally Posted by jhnkvn View Post
Actually, Chinoi is correct theoretically but TheGreenThing is correct practically. Wiring in series or in parallel won't impact real-world car electrical performance to a noticeable degree.

The ideal speaker is one without any electrical impedance. The shorter the wire, the closer it is to the "ideal" as resistivity is tied to the unit length of the conductor.
And remember grounding wires/battery/alternator are DC system so you cannot compare to a speaker which is an AC system, hence resistance is not impedance. Speakers will always have impedance because of the coils, you cannot make near-zero ohm to move a coil around a magnet.

Grounding kits helps in distributing the current flow thru multiple grounding contacts. Considering that most auto wires are just designed to run basic electrical accessories and they degrade over time(crimps, bonds,corossion, torque), installation of additional grounding would always be an advantage.

Imagine one thick wire with single contact vs multiple thin wire in multiple contact. You should be comparing firehose to a multiple garden hose.